The invention relates generally to an electrical machine, in particular a generator for a motor vehicle.
From U.S. Pat. No. 5,907,203, a generator for a motor vehicle is known in which a voltage regulator is connected electrically to the slip ring assembly. The generator has a cooling conduit, which extends past a voltage regulator. The voltage regulator includes a housing, a printed circuit board, and a regulator chip, which are mounted on a fastening plate. The fastening plate of the regulator directly adjoins the cooling air conduit. The cooling air conduit is created by a spacer element, which spaces the fastening plate apart from the generator housing. A disadvantage of this embodiment is that the printed circuit board with the regulator chip is mounted on an additional fastening plate. The heat transfer to the aspirated cooling air is restricted by the fastening plate on which the regulator chip is mounted. Accordingly, the cooling air flow does not come into direct contact with the printed circuit board or the regulator chip. Moreover, because of the spacer element, a larger installation space is needed, which adversely affects the size of the generator. Moreover, higher production costs result from the additional costs for material and assembly.
It is accordingly the object of the invention to create an electrical machine, in particular a generator, with improved cooling of the regulator.
The nucleus of the invention is that the chip holder is disposed such that it is bathed at least in part directly by the cooling air flow. In accordance with further features of the invention, it is proved advantageous to dispose the chip holder at a point where the speed of the cooling air flow is especially high, because the heat transfer is quite pronounced at that point.